A Magnetorheological Energy Absorber for Enhanced Crashworthiness in Drop-Induced Impacts

Abstract

This thesis uses a multidisciplinary approach to investigate the enhanced crashworthiness of a magnetorheological energy absorber (MREA). Magnetorheological (MR) fluids have been considered for use in crashworthiness applications because they can be modified to adjust for parameters such as an occupant’s weight or the impact velocity of a crash. This study first reviews an existing soft landing control algorithm for an MREA vertically stroking crew seat and applies it to several crash scenarios. The combined addition of a bumper and optimized yield force is found to successfully reduce the jerk at the end of the MREA stroke without introducing new discontinuities in the acceleration profile. Secondly, this study explores the use of mesocarbon microbeads (MCMBs) in MR fluids. The MCMBs are found to increase the yield force produced in an MR damper. An endurance study further reveals the durability of the yield force-enhancing effect up to 100,000 cycles.